MINA, Saudi Arabia - At least 717 pilgrims were killed on Thursday in a crush outside the Muslim holy city of Mecca, the Saudi authorities said, the worst disaster to strike the annual haj pilgrimage in 25 years.
At least 863 others were injured at Mina, a few kilometers east of Mecca, when two large groups of pilgrims arrived together at a crossroads on their way to performing the "stoning of the devil" ritual at Jamarat, Saudi civil defense said.
Thursday's disaster was the worst to occur at the pilgrimage since July 1990, when 1,426 pilgrims were crushed to death in a tunnel near Mecca. Both stampedes occurred on Eid al-Adha (Feast of the Sacrifice), Islam's most important feast and the day of the stoning ritual.
Photographs published on the Twitter feed of the Saudi civil defense on Thursday showed pilgrims lying on stretchers while emergency workers in high-visibility jackets lifted them into an ambulance.
The haj, the world's largest annual gathering of people, has been the scene of numerous deadly stampedes, fires and riots in the past, but their frequency was greatly reduced in recent years as the government spent billions of dollars upgrading and expanding haj infrastructure and crowd control technology.
Safety during haj is a politically sensitive issue for the kingdom's ruling Al Saud dynasty, which presents itself internationally as the guardian of orthodox Islam and custodian of its holiest places in Mecca and Medina.
Saudi Arabia's Interior Minister Prince Mohammed bin Nayef bin Abdelaziz said a committee would carry out an investigation into the disaster, Saudi state television reported.
Unverified video posted on Twitter showed bodies, clad in the white toweling of those undertaking haj, lying on the ground by the side of the road, surrounded by debris, as pilgrims and rescue workers attempted to revive them.
Iranian state news agency IRNA said at least 47 Iranians were among the dead and cited Iran's Deputy Foreign Minister Hossein Amir Abdollahian as saying Saudi Arabia was responsible.
Street 204, where the crush occurred, is one of two main arteries leading through the camp at Mina to Jamarat, the site where pilgrims ritually stone the devil by hurling pebbles at three large pillars. In 2006, at least 346 pilgrims died in a stampede at Jamarat.
"Work is underway to separate large groups of people and direct pilgrims to alternative routes," the Saudi Civil Defense said on its Twitter account.
It said more than 220 ambulances and 4,000 rescue workers had been sent in to help the injured. Some of the wounded were evacuated by helicopters.
An Arab pilgrim who did not want to give his name said he had hoped to perform the stoning ritual later on Thursday afternoon but was now too frightened to risk doing so.
"I am very tired already and after this I can't go. I will wait for the night and if it not resolved, I will see if maybe somebody else can do it on my behalf," he said.
Efforts to improve safety at Jamarat have included enlarging the three pillars and constructing a three-decker bridge around them to increase the area and number of entry and exit points for pilgrims to perform the ritual.
More than 100,000 police and thousands of video cameras are also deployed to allow groups to be dispersed before they reach dangerous levels of density.
"Please pilgrims do not push one another. Please leave from the exit and don't come back by the same route," an officer kept repeating through a loudspeaker at Jamarat.
Two weeks ago 110 people died in Mecca's Grand Mosque when a crane working on an expansion project collapsed during a storm and toppled off the roof into the main courtyard, crushing pilgrims underneath.
For a map locating the site of the crush, see here.
(Additional reporting by Omar Fahmy in Cairo and Bozorgmehr Sharafedin in Dubai; Writing by Sami Aboudi and Angus McDowall,; Editing by Dominic Evans and Raissa Kasolowsky)